Objective:To investigate the prevalence and related factors of dental caries in 3-year-old children in the Development District in Dalian.Methods:A multi-stage,randomized,cluster sampling method was used in the cross-sectional study.All 3-year-old children in the selected 15 kindergartens were invited to take part in the oral health examination conducted by 3 calibrated examiners.The WHO recommended caries diagnosis criteria were used.The structured questionnaire including the information of children's oral hygiene habits,dietary habits,parents' oral health knowledge and socioeconomic status was completed by the parents.Results:1 220 3-year-old children completed the clinical oral examination and 964 children's parents(79.0％) finished the questionnaire.The caries prevalence in 3-year-old children was 62.8％,and the mean dmft and dmfs scores were 3.40 and 7.34,respectively.No differences in the prevalence of caries,mean dmft and dmfs scores were found between boys and girls(P ＞0.05).Logistic regression analysis showed that the frequency of sweets and sugar-containing beverages consumption(P＜0.05),parents'education level(P＜0.05) were significantly related to the caries prevalence.Conclusion:The prevalence and severity of dental caries in 3-year-old children in Dalian Development District were high and the frequency of consumption sugar-containing foods and beverages,parents'education level were related to the decay prevalence.

Background and purpose: The incidence and mortality of lung cancer ranked first in China. This study aimed to describe lung cancer survival in Shanghai, and provide background information for cancer prevention and treatment evaluation. Methods: Data of lung cancer cases diagnosed during 2002-2006, follow-up information and death report were collected from Shanghai Cancer Registry. Life table method and Ederer Ⅱ were used to calculate observed survival (OS) and relative survival (RS) respectively. Related demographic characteristics and status were also analyzed to present the survival situations of the lung cancer survivors in Shanghai. Results: In this study, 41802 lung cancer cases were included in analysis. The 5-year OS and RS for lung cancer were 13.75% and 20.23% respectively, and median survival time was 318 days. Survival rate was higher among females than males, with the 5-year OS of 15.49% and 13.00% respectively. The 5-year OS was higher among suburban residents (14.25%) than urban residents (13.23%). Survival rates decreased with increasing age and advanced stage. Patients aged 0-34 had a 5-year OS of 38.21%, while patients aged above 75 had a 5-year OS of 5.48%. Patients diagnosed with stage Ⅰ had a 5-year OS of 55.47%, while patients diagnosed with stage Ⅳ had a 5-year OS of 5.27%. Survival of lung cancer patients differed by tumor histological subtype. The 5-year OS of squamous lung cancer (24.40%) was higher than other histological types, followed by adenocarcinoma (22.26%), large cell (20.27%) and small cell lung cancer (12.22%). From 1972-1976 to 2002-2006, the 5-year OS of urban male patients increased from 6.8% to 12.4%, and 5-year OS of urban female patients increased from 7.3% to 14.9%. Analysis of RS gave the similar results. Conclusion: During the past 30 years, survival rate of lung cancer patients in Shanghai improved steadily, and the survival condition is above average among different countries and areas. However, survival rate of lung cancer is still low compared with other types of cancer. Future focus should be placed on the control of tobacco smoking, early detection by low-dose helical computed tomography and targeted therapy to further improve lung cancer survival.